If you are like me, then your Facebook feed has recently begun filling up with a lot of black and white images. One of this year's most popular Instagram meme's, The '7 Day Black and White Challenge', encourages people to share black and white images every day for 7 days, and challenge their friends to do the same - which I think is great because I love black and white.

However, the trend got me thinking about what actually makes for a good black and white picture. Does converting any image to greyscale automatically make it more serious, arty, better as a composition? Or, is switching to black and white just a pretentious hack to save a mediocre color image?

I think the answer lies somewhere in-between. Some types of images unquestionably lend themselves to black and white, whereas others are better left in color. But, unlike in the past when shooting in monochrome was decided by the film loaded in your camera at the time you took the picture, now the choice is just as likely made at the time of posting or sharing an image. I thought it would be worth delving in a little deeper to why some images seem to get so much better when desaturated.

With that, here are 7 tips you may wish to consider the next time you are choosing black and white for your image.

Tip #1 - Removing Color Can Help Focus Your Subject

Color tends to be the first thing that to grab our attention in an image. Regardless of how compelling a particular subject is, the colors in an image are going to immediately draw your attention. This can be a good thing or bad depending on your subject and what you are trying to say about it.

With all the conflicting color information removed, our main subject - the street vendor - stands out more.

When we convert an image to black and white, we are effectively throwing out a huge chunk of visual information. If we think about pictures as telling a story about a subject, then we need to ask ourselves if the color information is helping tell the story or distracting from it.

Tip #2 - Use Black and White to Explore Abstraction

The Oxford dictionary offers the following definition for abstraction: the quality of dealing with ideas rather than events, freedom from representational qualities in art.

Black and white images are by their nature, abstract. They are one step removed from being a realistic depiction of a natural scene.

When we transform a color image into black and white, we shift focus from the realistic nature of the subject and allow ourselves to see the underlying compositional elements more clearly. We start to recognize and focus on specific shapes and forms underpinning the composition.

In the image above, the child in the image - while still the main subject - shifts from being the sole focus. Instead, the dynamic shapes and composition of the landscape are what jump out at us.

Tip #3 - Focus on Texture.

One type of picture that lends itself very well to black and white treatment, is one where the story is largely told through texture. Texture is the physical surface properties of an object - its smoothness or roughness. Texture is about whether we perceive the object as hard, soft, abrasive, wet, etc.

When I originally shot this picture of cliff divers in Vancouver, I was just trying to get a good composition of kids rather perilously launching themselves into the water. When I processed the image, it occurred to me that the story was really about texture; The contrast between the rough surface of the rocks, the softness of the diver's skin and the black wet turbulent water below were what told the story and enhanced the feeling of danger.

Texture is very much a feature of the 'luminosity' (light or dark) components of an image. In fact, as you can see from the example here, it is very difficult to get a sense of depth from color information alone. I think that's why images where there is a lot of texture often work well in black and white. The color is just getting in the way.

Tip #4 -Explore Contrast and Tonality

Contrast plays a big role in any image, but in a black and white photograph, it is particularly important to consider. I would recommend playing around with the contrast settings when you shoot or convert your images to monochrome.

It is generally accepted that black and white images tend to look visually pleasing when they include areas of pure black and pure white. However, the amount of white and black, and range of tones in between white and black are very much a subjective and aesthetic choice. Tonality can make a huge impact on the mood and feel of your image.

More contrasty images tend to feel more dynamic, 'punchy' or dramatic. Less contrasty images can feel more reflective, softer, more subtle. When choosing how much contrast to add, remember it's not a matter of what is 'right or wrong' but rather what you feel best helps convey the story the image is telling.

If you use a photo editing package such as Adobe Lightroom you probably already aware of some of the many controls available for playing around with brightness and contrast, but even most social media apps such Instagram allow you some control over the contrast settings.

Tip #5 - B&W Images Feel Timeless

There is no doubt that there is a nostalgic, timeless quality to black and white. We have so many strong associations with it as both a historical and news media. The instant we see an image in black and white - even a contemporary scene - we seem to forgive a lot of the humdrum modern details. The picture becomes locked in 'another' time. It becomes a piece of historical reportage.

I love this image my wife took of me and my son beside a washed out lake in Vancouver. It's a strong image with a great story to start with, but for me, bringing it into black and white just transforms it. The distracting day-glow safety patch on my son's jumper disappears, and the somber black and white treatment serve to enhance the melancholy mood and transport us to another time.

Tip# 6 - Explore Postive and Negative Space

I like to use a lot of silhouettes in my images. Partly this is down to my style, but also because I like playing with positive and negative space in my compositions, and this is something that works particularly well in black and white.

Negative and positive space is about the space 'filled' by a subject - such as a person or an object (the positive space) - and the and the 'empty' or negative space surrounding it.

Often we focus our attention on the positive spaces; on the content. But when we look at the negative space we are concentrating on the cookie cutter shape surrounding our content.

That isn't to say subjects have to be in silhouette to make use of negative space - just that its a good idea to think about the space surrounding your subject as much as the subject itself and black and white offers a great way to emphasize it.

Tip #7 - 'Look into the light'

Or better still, beside it... As discussed, black and white images often work well when the photographer has considered elements of shape, negative space, tonal range, and texture. Images that are suited well to black and white tend to have a light source that emphasizes these elements.

One way to help achieve this is lighting from the back or sides. This darkens shadows, defines the form (the '3d' volume of an object) and brings out surface texture.

In the above image, the strong backlighting pushes the subjects into silhouette, emphasizing the negative space in the composition, while at the same time the hard shadows bring out the texture of the wet beach.

In this portrait, the main and secondary light sources come from the sides creating depth, drama and emphasizing texture.

A popular rule of thumb many photographers follow: When shooting for color, aim for softer less-contrasty light sources that positioned in front of the subject. This will bring out the subtlety of colors, and soften harsh shadows. For black and white the opposite is true - aim to have the light source either behind or to the side your main subject in order to pump up the shadows and emphasize form and texture.

When Black and White Doesn't Work

On a final note, remember there are plenty of times when going to black and white just doesn't work. This is particularly the case when the picture is inherently all about the color. For example, nothing makes food seem utterly unpalatable than to drain it of all those color cues that we associate with flavor and richness.

In Conclusion

Some images work great in black and white, and some don't. Shifting an image to monochrome can breath new life into some images, or completely kill others. It depends on the content of the original, the story you are trying to tell, and the choices you make about tone and contrast.

I hope I was able to share a few ideas with you about what sort of images work well in black and white, and offer some thoughts on how to further enhance your pictures.